Well-casing spear



R. A. WILSON.

WELL CASING SPEAR.

APPLICATION FILED AUG-2, 1920.

. 1 8,766 Patented June 6, 1922.

FATENT FFHQE.

ROBERT A. WILSON, 01? DALLAS,- TEXAS, ASSIGNOR TO THE GUIBERSON CORPORA- TI ON, OF DALLAS, TEXAS, A CORPORATION OF DELAWARE.

WELL-CASING srnan.

Specification of Letters Patent. 7 Patented J 11116 6 1922 Application fi1e6. August 2, 1920. Serial No. 400,584.

To all whom it may 0011mm V Be it known that I, Ronnn r A. WILsoN, a citizen of the United States, residing at Dallas, in the county'of'Dallas and State of Texas, have invented certain new and useful Improvements in VVell-Casing Spears, of which the following is a specification.

"This invention has to do with well casing spears. I

The purpose of the invention is to provide a spear that can be engaged at any desired point in the casing, or released'at will and then raised or lowered in the well, without distance from the head and is fastened in the use of trip devices or the necessity of first bringing it tothesurface. A further result sought is to produce a spear of a substantial and simple nature in which a head, which may have water courses, may be employed and the use of catches, release pins and tripping devices, obviated. Another feature is the reduction of the number of parts usually employed.

. the diameter of the spear head; By impart- In carrying out the invention I provide a mandrel having a spear head at its lower end, said head having a larger diameter than the mandrel. A spring sustained weight is mounted on the mandrel. The lower end of the weight is pivotally connected with casing engaging slips, slidably confined on thehead and normally within ,Wltll arcuate teeth disposed circumferening a quick upward movement to the mandrel the slips are forced outward into engagement with the casing owing to the inertia of the weight. The spear is released and the slips withdrawn, by forcing the mandrel downward. Other featuresof the invention will be hereinafter pointed out.

*The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in which an exampleof the invention is shown, and wherein:

Fig. 1 is a view in elevation of a device constructed'in accordance with my invention.

Fig. 2 is an enlarged View of the device, the weight being shown partly in section,

' Fig. 3 is a cross-sectional detail on the line 3'3 of Fig. 2,

Fig. 4 is a cross-sectional detail 'on the line 4-4 of Fig. 2, and

Fig. 5 is a cross-sectional detail. on the n 5-45 of Fig. 2.

In the drawings the numeral 10 designates a cylindrical mandrel which has a rounded spear head 11 at its lower end, the head being larger in diameter than the mandrel. At its upper end the mandrel has a tapered screw-threaded stub 12 by which the mandrel maybe joined to the support by which it is lowered into the well. Just below the stub the mandrel is provided with an angular wrench grip 18 so that it may be engaged by a suitable tool for screwing'the stub 12 into the support.

A'collar 14: surrounds the mandrel a short position. This collar supports a coiled spring 15 which surrounds the mandrel. A weight in. the form of a sleeve 16 is disposed on the mandrel and has acounter-bore '17 receiving the spring which latter supports the sleeve at its upperend. At its lower end I the sleeve has depending cars 18 andbetween, each pair of cars the upper end ofa .link 19 is pivoted. I have shown three of these links equally spaced around the mandrel and below the collar 14:, however, the invention is not to be limited to this number. Each link has its lower end pivoted vin a pair of cars 20 provided on the upper ends of slips 21.

Eachslip 21 has its outer face provided tially of said spear and formed so as to engage 111 a surface when the spear is elevated as is usual in casing spears. The

inner faces22 of the slips are'inclined inwardly and upwardly SO lS to conform to inclined 'guideways 23 formed on the upper port-ion of'the head 11. It will be noted that the guideways 23 begin substantially at the point of greatest diameter of the head 11, and extend to the upper end of the held against radial displacement, but are free to slide up and down the guideways. However, the invention is not to be limited to is manner of co fi g he s ps an any retract the slips.

When the spear islowered into the well the slips will be in their normal position which is at the upper ends of the guideways 23, and in thisposition they will be well within the mean diameter on the head 11. They aresupported in this position by means of the spring 15 which holds the weight sleeve 16 in an elevated position. It will be seen that the-spear may be lowered to the desired point inthe well without catching on'the side ofthe casing. When it is desired to engage the spear with the casing it is simply necessary to impart a sudden upward m0vement to the mandrel 10. This results in the slips 21'being forced outwardly so that their teethengage in the wall of the casing. This is due to the fact that the inertia of the weight 16 tends to keep it in a state of rest.

Thus when the said upward movement is imparted, the spring 15 will be compressed and the head 11 will move upwardly. When the head 11 moves upwardly the inclined guideways 23 riding up the faces22 of the slips, will force said slips outwardly until their teeth bite into the casing. The spring, of course, must'be of such a tension as tosupport the slips but not resist the inertia of the weight 16.

When it is desired to release the slips from engagement with the casing itismerely necessary to force the mandrel 10 downwardly so that the guidewaysQS are moved down the faces 22 whereby the slips are withdrawn. iVhen this is done the compression spring 15 will be freed and will tend to elevate the weight 16 whereby the slips will be carried to their normal position. From the foregoing it will be apparent that the spear may be engaged with the casing at any point desired and may be released therefrom at will;

and further after beingreleased said spear may be raised or loweredin the well to any point and then re-engaged with the casing if desired, all of which is accomplished without bringing the spear to the surface to be adjusted or set. It is pointed. out that the action of the slips is positive and each has a positive bearing on the headll. The parts are of such a nature thatth'ey may be strongly constructed andwill undergo heavy "duty without givingtrouble, thus increasing the life of' the spear and making repairs not only "infrequent, buteasy.

While I have shown a compression spring it is to be understood that any other kind of spring could be used and the invention is not to be limited to any particular kind of spring. Various structures could be evolved for resiliently sustaining the weight and the invention includes all such modifications as come within the scope of the appended claims.

lVhatI claim, is:

1. In a well casing spear, a mandrel, a head carried bythe mandrel, radially displaceableslips mounted on the head, and a resiliently sustained weight mounted on the mandrel and having connection with the slips.

' 2.111 a well casing spear, a mandrel, a

head carried by the mandrel, said headhaving inclined portions, slips mounted on said inclined portions of the head, and aresiliently sustained weight mounted onthe mandrel and connected with the slips, the head and weight being adaptedtoundergorelative movementwh'e'reby the slips'move radially. V

3. In a well casing spear, a'mandrel, a

'headfixed on the lower end of the mandrel,

said head having inclined guideways, slips confined to a vertical movement on the guideways, and means for checking a relative upward movement of the slips when th mandrel and headaresuddenly moved upwardly.

4. In a well casing spear, a mandrel, a

head carried at the lower end of the mandrel and provided with inclined guideways, slips slidable on said guideways, a springsupported weight member surrounding the mandrel, and pivoted connections between the weight member and the slips.

"5. In a well casing spear, a mandrel, a

head at the lower end of the mandrel, radially displaceable slips mounted on the head, a colled spring supportedon the mandrel above the head, a weight sleeve supported on the spring and surrounding the mandrel, and pivoted links connecting the sleeve with the slips.

6. In a well casing spear, a mandrel, an enlarged head fixed at the lower end of the mandrel, said head-having inclined guideways, retaining ribs extending longitudinally of said guideways, slips slidably confined on the guideways and receiving said ribs, a collar mounted on the mandrel above the head, a coiled spring supported on the collar and surrounding the mandrel, a weight sleeve surrounding the spring and having its upper end supported thereby, and links pivotally connecting the lower end of the sleeve with the upper ends of the slips, whereby said slips are supported.

7. In a well casing spear, a pluralityof gripping slips, a support having inclined faces on which the slips are mounted to slide,

a weight member, a coiled spring on which a weight sleeve, a coiled spring telescoping the member is sustained, and connections into the sleeve and supporting the same, between the slips and the weight member and pivoted connections between the sleeve 10 pivoted thereto. and the slips sustaining the latter.

5 8. In a well casing spear, a plurality of In testimony whereof I ailix my signagripping slips, a support having inclined ture. faces on which the slips are mounted to slide, ROBERT A. WILSON: 

